Feed through interconnect assembly for an implantable stimulation system and methods of making and using

ABSTRACT

A stimulation system includes an implantable pulse generator having a sealed chamber and an electronic subassembly disposed in the sealed chamber. Feed through pins are coupled to the electronic subassembly and extend out of the sealed chamber. Feed through interconnects are coupled to the electronic subassembly via the feed through pins. At least one tab is disposed on at least one feed through interconnect. The tab(s) are configured and arranged to flex away from the feed through interconnect and against a side of the feed through pin. 
     A feed through interconnect assembly includes an assembly frame; feed through interconnects extending from the assembly frame; a first contact pad and a second contact pad disposed on at least one of the feed through interconnects; and a tab formed on a first contact pad of at least one of the feed through interconnects.

CROSS-REFERENCE TO RELATED APPLICATIONS

This utility patent application is a continuation of U.S. patentapplication Ser. No. 13/525,049 filed Jun. 15, 2012 which is adivisional of U.S. patent application Ser. No. 11/532,844, filed Sep.18, 2006, both of which are incorporated herein by reference.

FIELD OF THE INVENTION

The invention is directed to implantable stimulation systems. Inaddition, the invention is directed to implantable stimulation systemshaving feed through interconnects, and methods of making the devices.

BACKGROUND OF THE INVENTION

Stimulation systems have been developed to provide therapy for a varietyof disorders, as well as other treatments. For example, stimulationsystems can be used in neurological therapy by stimulating nerves ormuscles, for urinary urge incontinence by stimulating nerve fibersproximal to the pudendal nerves of the pelvic floor, for erectile andother sexual dysfunctions by stimulating the cavernous nerve(s), forreduction of pressure sores or venous stasis, etc.

Stimulation systems, such as the BION device (available from AdvancedBionics Corporation, Sylmar, Calif.), have exposed electrodes and asmall, often cylindrical, housing that contains the electronic circuitryand power source that produce electrical pulses at the electrodes forstimulation of the neighboring tissue. Other stimulators, such as thePrecision® rechargeable stimulator, in combination withlinear/percutaneous leads or paddle type leads are used to stimulate thespinal cord for treating intractable chronic pain. It is preferable thatthe electronic circuitry and power source be held within the housing ina hermetically-sealed environment for the protection of the user and theprotection of the circuitry and power source. Once implanted, it isoften preferable that the stimulation system can be controlled and/orthat the electrical source can be charged without removing thestimulation system from the implanted environment.

BRIEF SUMMARY OF THE INVENTION

One embodiment is a stimulation system that includes an implantablepulse generator having a sealed chamber and an electronic subassemblydisposed in the sealed chamber. Feed through pins are coupled to theelectronic subassembly and extend out of the sealed chamber. Feedthrough interconnects are coupled to the electronic subassembly via thefeed through pins. At least one tab is disposed on at least one feedthrough interconnect. The tab(s) are configured and arranged to flexaway from the feed through interconnect and against a side of the feedthrough pin.

Another embodiment is a feed through interconnect assembly that includesan assembly frame; feed through interconnects extending from theassembly frame; a first contact pad and a second contact pad disposed onat least one of the feed through interconnects; and a tab formed on afirst contact pad of at least one of the feed through interconnects.

Yet another embodiment is a method of making a stimulation device bycoupling a feed through interconnect assembly to a lead connector. Thefeed through interconnect assembly has an assembly frame, feed throughinterconnects extending from the assembly frame, a first contact pad anda second contact pad disposed on at least one of the feed throughinterconnects, and a tab formed on a first contact pad of at least oneof the feed through interconnects. The feed through interconnectassembly is coupled to an implantable pulse generator which has a sealedchamber, an electronic subassembly disposed in the sealed chamber, andfeed through pins coupled to the electronic subassembly and extendingthrough the sealed chamber.

BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting and non-exhaustive embodiments of the present invention aredescribed with reference to the following drawings. In the drawings,like reference numerals refer to like parts throughout the variousfigures unless otherwise specified.

For a better understanding of the present invention, reference will bemade to the following Detailed Description, which is to be read inassociation with the accompanying drawings, wherein:

FIG. 1 is a schematic perspective view of one embodiment of astimulation system, according to the invention; and

FIG. 2 is a schematic perspective view of one embodiment of a feedthrough interconnect assembly, according to the invention;

FIG. 3 is a schematic perspective view of the feed through interconnectassembly of FIG. 2 coupled to an implantable pulse generator and leadconnectors, according to the invention;

FIG. 4 is a schematic close-up perspective view of a portion of the feedthrough interconnect assembly of FIG. 3 coupled to the implantable pulsegenerator;

FIG. 5 is a schematic perspective view of one embodiment of animplantable pulse generator coupled to lead connectors via feed throughinterconnects, according to the invention; and

FIG. 6 is a schematic overview of components of a stimulation system,according to an embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The invention is directed to implantable stimulation systems. Inaddition, the invention is directed to implantable stimulation systemshaving feed through interconnects, and methods of making the devices.

Examples of suitable stimulators and stimulation systems can be foundin, for example, U.S. Pat. Nos. 6,609,032; 6,181,969; 6,516,227;6,609,029; 6,741,892; 7,244,150; 7,672,734; and 7,974,706; and U.S.Patent Application Publication No. 2007/0150036, all of which areincorporated herein by reference.

A stimulation system can include an electrode lead coupled to animplantable pulse generator. The implantable pulse generator may includea housing and an electronic subassembly disposed (and, preferably,hermitically sealed) within the housing. The implantable pulse generatormay further include feed through pins that are coupled to the electronicsubassembly and that extend through the housing. The lead may haveseveral lead contacts that connect to individual feed through pins onthe implantable pulse generator. For example, the lead may have a leadcontact for each electrode. The lead contacts may connect to the feedthrough pins on the implantable pulse generator via a lead connector.

A wire may be used to couple the lead connector to the feed through pinson the implantable pulse generator. However, using a wire can presentmanufacturing complications such as maintaining the position of the wirewhile attaching the wire to the feed through pins and/or the leadconnector. In addition, using a wire may present failure points at theweld junctions of the wire to the feed through pins as well as at theweld junction of the wire to the lead connector. Furthermore,manufacturing constraints can impose restrictions on the diameter of thewire. Restricting the diameter of the wire may affect the fatigue lifeof the wire, resulting in premature failure and shortening of thedevice's longevity.

Longer feed through pins that directly connect to the contacts of thelead connector may also be used. However, a longer feed through pin mayresult in additional force being applied directly to the feed throughpin. This additional force may also damage seals that may be present inthe implantable pulse generator.

A feed through interconnect assembly can be used to couple theimplantable pulse generator feed through pins to the lead connector. Thefeed through interconnect assembly can include, for example, an assemblyframe, feed through interconnects extending from the assembly frame,contact pads disposed on the feed through interconnects, and tabs formedon the contact pads of the feed through interconnects. One or moreoptional indexing holes may be located on the assembly frame. Inaddition, one or more optional braces may couple the assembly frame tothe feed through interconnects extending from the assembly frame.

A feed through interconnect assembly can be used to make a stimulationsystem. The feed through interconnect assembly may be coupled to atleast one feed through pin of an implantable pulse generator. The feedthrough interconnect assembly may further be coupled to at least onelead connector. Before, during, or after the coupling of feed throughinterconnect assembly to the feed through pin(s) of the implantablepulse generator and the lead connector(s), some components of the feedthrough interconnect assembly may be removed. For example, the assemblyframe may be removable. Alternatively, or additionally, braces thatcouple the feed through interconnects to the assembly frame may beremovable.

FIG. 1 illustrates schematically one embodiment of a stimulation system100. The stimulation system includes an implantable pulse generator 102and a lead 106. A distal portion of the lead body contains one or moreelectrodes (e.g., an electrode array 104). It will be understood thatthe stimulation system can include more or different components and canhave a variety of different configurations including thoseconfigurations disclosed in the stimulation system references citedherein. The stimulation system or components of the stimulation system,including the lead 106 and the implantable pulse generator 102, areimplanted into the body. The implantable pulse generator 102 typicallyincludes a housing 114 with an electronic subassembly 110 and, in atleast some embodiments, a power source 120, disposed within a sealedchamber 108 in the housing 114.

One embodiment of a feed through interconnect assembly 130 isillustrated in FIG. 2. A feed through interconnect assembly 130 may beused to couple the lead connector(s) 160 to the feed through pin(s) 144of the implantable pulse generator 102, as illustrated in FIG. 3. A feedthrough interconnect assembly 130 may include an assembly frame 132,feed through interconnects 134 extending from the assembly frame 132,contact pads 136 disposed on the feed through interconnects 134, andtabs 138 formed on the contact pads 136 of the feed throughinterconnects 134. One or more optional indexing holes 142 may belocated on the assembly frame 132. In addition, one or more optionalbraces 140 may couple the assembly frame 132 to the feed throughinterconnects 134 extending from the assembly frame 132.

An assembly frame 132 can be made of any material including, forexample, stainless steel materials (e.g., 316L and MP35N), platinum,platinum/iridium, titanium, other metals and alloys, polymers, and thelike. The assembly frame may have any shape including, for example, asquare, rectangular, circular or elliptical shape. Typically, theassembly frame 132 is removable from the feed through interconnects 134.For example, the assembly frame 132 may be removed from the feed throughinterconnect assembly 130 either before, during, or after the feedthrough interconnect assembly 130 is coupled to the lead connector(s)160 or the feed through pins 144 of the implantable pulse generator 102(see FIG. 3).

One or more indexing holes 142 may be located on the assembly frame 132.The indexing holes 142 may have any shape. There may be any number ofindexing holes including, for example, zero, one, two, three, four,five, six, seven, eight, nine, or ten. As will be recognized, othernumbers of indexing holes 142 are also possible. The indexing hole(s)may be located anywhere on the assembly frame 132. Preferably, theindexing holes 142 are shaped and located such that the indexing holesaid in positioning the feed through interconnect assembly 130 withrespect to the implantable pulse generator 102 during the manufacturingprocess.

The feed through interconnects 134 can extend from the assembly frame132 in any desired arrangement. For example, the feed throughinterconnects 134 may extend from at least one side of the assemblyframe 132 towards the opposite side of the assembly frame asillustrated, for example, in FIG. 2. The feed through interconnects 134may extend from the assembly frame 132 either below, above or in theplane of the assembly frame 132.

Feed through interconnects 134 are made of any conductive material thatis preferably biocompatible. Suitable materials for feed throughinterconnects 134 include, for example, stainless steel materials (e.g.,316L and MP35N), platinum, platinum/iridium, titanium, other metals andalloys, polymers, and the like. The feed through interconnects 134 arepreferably made of a material that allows the feed through interconnects134 to be bent or otherwise re-positioned. Feed through interconnects134 may have any shape. Preferably, feed through interconnects 134 havea shape that allows the feed through interconnects 134 to couple thefeed through pins 144 of the implantable pulse generator 102 to the leadconnector(s) 160.

There may be any number of feed through interconnects 134 including, forexample, two, three, four, five, six, seven, eight, nine, ten, eleven,twelve, thirteen, fourteen, fifteen, sixteen, seventeen, eighteen,nineteen, twenty, twenty-one, or twenty-two feed through interconnects134. As will be recognized, other numbers of feed through interconnects134 are also possible. Preferably, the number of feed throughinterconnects 134 is equal to the number of feed through pins 144 (seeFIG. 3) of the implantable pulse generator 102.

In at least some embodiments, the feed through interconnects 134 arespaced apart at substantially uniform distances. For example, thedistance between the feed through interconnects 134 may vary by no morethan about 2.5 mm.

Feed through interconnects 134 may extend from more than one side of theassembly frame 132. For example, feed through interconnects 134 mayextend from two opposing sides of the assembly frame 132 as illustrated,for example, in FIG. 2. Feed through interconnects 134 may beinterleaved. For example, the feed through interconnects 134 extendingfrom the assembly frame 132 may alternate between feed throughinterconnects 134 extending from a first side of the assembly frame 132and feed through interconnects 134 extending from a second side of theassembly frame 132. One embodiment of interleaving feed throughinterconnects 134 is illustrated in FIG. 2. In FIG. 2, the feed throughinterconnects 134 alternate between feed through interconnects 134 a,134 c, 134 e, 134 g that extend from a first side of the assembly frame132 and feed through interconnects 134 b, 134 d, 134 f, and 134 h thatextend from a second side of the assembly frame 132. As will berecognized, in other embodiments feed through interconnects 134 may beinterleaved such that two, three, four or more feed throughinterconnects 134 extend from a first side of the assembly frame 132before alternating to feed through interconnects 134 extending from asecond side of the assembly frame 132.

Contact pads 136 are disposed on the feed through interconnects 134. Thecontact pads 136 may be made of any conductive material that ispreferably biocompatible including, for example, stainless steelmaterials (e.g., 316L and MP35N), platinum, platinum/iridium, titanium,other metals and alloys, polymers, and the like. The contact pads 136may have any shape including, for example, a square, circular,elliptical, or rectangular shape. The contact pads 136 may have a widththat is smaller, equal to, or greater than the width of the feed throughinterconnects 134.

One or two contact pads may be disposed on a feed through interconnect134. Preferably, two contact pads 136 are disposed on each feed throughinterconnect 134 as illustrated in FIG. 2. For example, a first contactpad 136 located on the distal end of the feed through interconnect 134can facilitate coupling of the feed through interconnect 134 with thefeed through pin 144 of the implantable pulse generator 102, while asecond contact pad 136 located on the proximal end of the feed throughinterconnect 134 can facilitate coupling of the feed throughinterconnect 134 with the lead connector 160. In one embodiment, a firstcontact pad 136 a located at a distal end of feed through interconnect134 a and a second contact pad 136 b located at a proximal end of feedthrough interconnect 134 a are illustrated in FIG. 2.

The feed through interconnects 134 may also include one or more tabs138. Preferably, the number of tabs 138 is equal to the number of feedthrough pins 144 (see FIG. 3) of the implantable pulse generator 102.Preferably, the tabs 138 are disposed on at least one contact pad 136 ofa feed through interconnect 134. In at least some embodiments, one tab138 is disposed on a first contact pad 136 for each feed throughinterconnect 134 as illustrated, for example, in FIG. 2.

Preferably, the tab 138 is formed to allow the tab 138 to flex anddistribute any forces transmitted to the feed through pin(s) 144 (seeFIG. 3). Preferably, the tabs 138 are configured and arranged such thatthe tabs 138 flex away from the contact pads 136 and against a side ofthe feed through pin 144 (see FIGS. 3 and 4). Preferably, the tabs 138are formed such that the tabs 138 have contact with the feed throughpins 144 when the feed through interconnects 134 are attached.

The feed through interconnect assembly 130 may include at least onebrace 140. In some embodiments, braces 140 are illustrated schematicallyin FIG. 2. The feed through interconnect assembly 130 may include anynumber of braces 140 including, for example, zero, one, two, three,four, five, six, seven, eight, nine, or ten braces 140. As will berecognized, other numbers of braces 140 are also possible. The brace(s)140 may be made of any material including, for example, stainless steelmaterials (e.g., 316L and MP35N), platinum, platinum/iridium, titanium,other metals and alloys, polymers, and the like. For ease ofmanufacture, the assembly frame 132, braces 140 and feed throughinterconnects can be formed of the same material.

A brace 140 is preferably located such that it couples at least one feedthrough interconnect 134 to the assembly frame 132. For example, a brace140 may couple at least one feed through interconnect 134 extending froma first side of the assembly frame 132 to the assembly frame 132 asillustrated in FIG. 2. Additionally or alternatively, a brace 140 maycouple at least one feed through interconnect 134 extending from asecond side of the assembly frame 132 to the assembly frame (see FIG.2). Preferably, the brace(s) 140 is capable of being removed from thefeed through interconnect assembly 130 after the feed throughinterconnect assembly 130 has been used to couple the feed through pins144 of the implantable pulse generator 102 to the lead connector 160.

The feed through interconnect assembly 130 may be made in any mannerincluding, for example, molding, stamping, or otherwise cutting theassembly from a sheet of material. The feed through assembly 130 mayoptionally be coated with a coating such as, for example, silicone,paralene, Teflon (ETFE, PFA, PTFE) or Kapton. The coating may optionallyprovide electrical isolation between, for example, adjacent connectorcontacts 170 or adjacent feed through pins 144.

Turning to FIG. 3, a method of making a stimulation device includescoupling a feed through interconnect assembly 130 to an implantablepulse generator 102. A method of making a stimulation device alsoincludes coupling a feed through interconnect assembly 130 to at leastone lead connector 160.

As set forth above, an implantable pulse generator 102 may include asealed chamber 108 (see FIG. 1). An electronic subassembly 110 may bedisposed in the sealed chamber 108 of the implantable pulse generator102. The implantable pulse generator 102 may also include feed throughpins 144 as illustrated in FIGS. 3 and 4. Preferably, the feed throughpins 144 are coupled to the electronic subassembly 110 and extendthrough the housing 114 to the sealed chamber 108.

Feed through pins 144 may be made of any conductive material that ispreferably biocompatible. Suitable materials for feed through pins 144include, for example, metals, alloys, conductive polymers, and the like.There may be any number of feed through pins 144 including one, two,three, four, five, six, seven, eight, nine, ten, eleven, twelve,thirteen, fourteen, fifteen, sixteen, seventeen, eighteen, nineteen,twenty, twenty-one, twenty-two or more feed through pins 144. As will berecognized, other numbers of feed through pins 144 are also possible.Preferably, the number of feed through pins 144 is equal to the numberof electrodes on the electrode array 104 (see FIGS. 3 and 5).

A first contact pad 136 disposed on each feed through interconnect 134may be coupled to each feed through pin 144 extending from the sealedchamber 108 of the implantable pulse generator 102. Even morepreferably, the tabs 138 formed on the contact pads 136 are coupled tothe feed through pins 144 of the implantable pulse generator 102. Thetabs 138 may be coupled to the feed through pins 144 in any mannerincluding, for example, by friction fit and/or by soldering, welding,and the like. In some embodiments, the tabs 138 could also be coupled tothe feed through pins 144 by the contact force due to flexing.

The feed through interconnect assembly 130 is coupled to at least onelead connector 160, as illustrated in FIG. 3. A lead connector 160 ispreferably configured and arranged to receive the proximal portion of alead. A lead connector 160 may be made of any biocompatible materialincluding, for example, silicone and polyurethane. One embodiment of amethod of making a lead connector 160 is disclosed in U.S. Pat. No.7,244,150, incorporated herein by reference.

The lead connector 160 includes connector contacts 170. The connectorcontacts 170 may be made of any conductive material that is preferablybiocompatible including, for example, metals, alloys, conductivepolymers, and the like. There may be any number of connector contacts170 including, for example, one, two, three, four, five, six, seven,eight, nine, ten, eleven, twelve, thirteen, fourteen, fifteen, sixteen,seventeen, eighteen, nineteen, twenty, twenty-one, twenty-two, or moreconnector contacts 170. As will be recognized, other numbers ofconnector contacts 170 are also possible. Preferably, the number ofconnector contacts 170 is equal to the number of feed through pins 144of the implantable pulse generator 102.

The feed through interconnect assembly 130 can be coupled to the leadconnector 160 in any manner, including soldering, welding and the like.Preferably, the feed through interconnect assembly 130 is coupled to theconnector contacts 170 of the lead connector 160. More preferably, atleast one feed through interconnect 134 is coupled to at least oneconnector contact 170. More preferably, at least one contact pad 136disposed on at least one feed through interconnect 134 is coupled to atleast one connector contact 170.

The position of the lead connector 160 may be altered after the leadconnector 160 is coupled to the feed through interconnect assembly 130.For example, as illustrated in FIG. 3, the lead connector 160 mayinitially be coupled to the feed through interconnect assembly 130 suchthat the position of the lead connector 160 does not substantiallyinterfere with the coupling of the feed through interconnect assembly130 to the feed through pins 144 of the implantable pulse generator 102.Then, after the feed through interconnect assembly 130 is coupled to thefeed through pins 144, the position of the lead connector 160 may bealtered as illustrated, for example, in FIG. 5. Feed throughinterconnects 134 that are flexible may be used to facilitatere-positioning of the lead connector 160. For example, flexible feedthrough interconnects 134 may wrap around at least a portion of thecircumference of the lead connector 160.

In some embodiments, components of the feed through interconnectassembly 130 may be removed before, during, or after coupling the feedthrough interconnect assembly 130 to the implantable pulse generator 102and/or to the lead connector 160. For example, the assembly frame 132may be removed from the feed through interconnect assembly 130 before,during, or after coupling the feed through interconnect assembly 130 tothe implantable pulse generator 102 and/or to the lead connector 160. Inanother example, at least one brace 140 may be removed from the feedthrough interconnect assembly 130 before, during, or after coupling thefeed through interconnect assembly 130 to the implantable pulsegenerator and/or to the lead connector 160.

Returning to FIG. 1, the housing is preferably resistant to moisturepenetration into the chamber containing the electronic subassembly andpower source. In some embodiments, water may diffuse through thehousing. Preferably, the diffused water is relatively pure, withoutsubstantial ionic content, as deionized water is relativelynon-conductive.

The housing 114 may be made of any biocompatible material including, forexample, glass, ceramics, metals, and polymers. In one embodiment, thehousing 114 of the implantable pulse generator is formed of a plasticmaterial that resists the transport of moisture into the interior of thehousing and is sufficiently sturdy to protect the components on theinterior of the housing from damage under expected usage conditions.Preferably, the material of the plastic housing is a hydrophobic polymermaterial. The housing 114 may include additives such as, for example,fillers, plasticizers, antioxidants, colorants, and the like. Thethickness of the walls of the housing may also impact the moisturepermeability of the housing. A minimum thickness needed to achieve aparticular degree of resistance to moisture transport will often dependon the material selected for the housing, as well as any additives.

Optionally, the housing 114 can be covered, in full or in part, with acoating. The coating can be provided to improve or alter one or moreproperties of the housing 114 including, for example, biocompatibility,hydrophobicity, moisture permeability, leaching of material into or outof the housing, and the like. In one embodiment, a coating can beapplied which contains a compound, such as, for example, a drug,prodrug, hormone, or other bioactive molecule, that can be released overtime when the stimulator is implanted. (In another embodiment, thehousing itself may include such a compound to be released over timeafter implantation.)

In one embodiment, a conductor or conductors (not shown) couple theelectrode(s) 154 on the distal portion of the lead 106 to theimplantable pulse generator 102. The conductors can be formed using anyconductive material. Examples of suitable materials include, forexample, metals, alloys, conductive polymers, and conductive carbon. Inone embodiment, the conductors are insulated by an insulating material.The insulating material may be any material that is a poor conductor ofan electrical signal, including, for example, Teflon™, non-conductivepolymers, or metal oxidation that is poor in electrical conductivity.

The body of the lead 106 may be made of any biocompatible materialincluding, for example, silicone, polyurethane, polyetheretherketone(PEEK), epoxy, and the like. The lead body may be formed by any processincluding, for example, molding (including injection molding), castingand the like. In one embodiment, a method of making an array body isdisclosed in U.S. patent application Ser. No. 11/319,291, which isincorporated herein by reference. The distal portion of the lead canhave any shape including, for example, a circular, elliptical, square orrectangular shape. FIG. 1 illustrates a paddle lead but it will berecognized that other types of leads, such as percutaneous leads (forexample, leads with ring electrodes) can be used.

Electrodes 154 are disposed on the array body. The electrodes 154 can bemade using any conductive material. Examples of suitable materialsinclude, for example, metals, alloys, conductive polymers, andconductive carbon. The number of electrodes 154 disposed on the arraybody may vary. For example, there can be two, three, four, five, six,seven, eight, nine, ten, eleven, twelve, thirteen, fourteen, fifteen,sixteen, or more electrodes 154. As will be recognized, other numbers ofelectrodes 154 may also be used.

FIG. 6 is a schematic overview of one embodiment of components of astimulation system, including an electronic subassembly 110 (which mayor may not include the power source 120), according to the invention. Itwill be understood that the stimulation system and the electronicsubassembly 110 can include more, fewer, or different components and canhave a variety of different configurations including thoseconfigurations disclosed in the stimulator references cited herein. Someor all of the components of the stimulation system can be positioned onone or more circuit boards or similar carriers within a housing of astimulator, if desired.

Any power source 120 can be used including, for example, a battery suchas a primary battery or a rechargeable battery. Examples of other powersources include super capacitors, nuclear or atomic batteries,mechanical resonators, infrared collectors, thermally-powered energysources, flexural powered energy sources, bioenergy power sources, fuelcells, bioelectric cells, osmotic pressure pumps, and the like includingthe power sources described in U.S. Pat. No. 7,437,193, incorporatedherein by reference.

As another alternative, power can be supplied by an external powersource through inductive coupling via the optional antenna 124 or asecondary antenna. The external power source can be in a device that ismounted on the skin of the user or in a unit that is provided near thestimulator user on a permanent or periodic basis.

If the power source 120 is a rechargeable battery, the battery may berecharged using the optional antenna 124, if desired. Power can beprovided to the battery 120 for recharging by inductively coupling thebattery through the antenna to a recharging unit 210 (see FIG. 6)external to the user.

In one embodiment, electrical current is emitted by the electrodes 154to stimulate motor nerve fibers, muscle fibers, or other body tissuesnear the stimulator. The electronic subassembly 110 provides theelectronics used to operate the stimulator and generate the electricalpulses at the electrodes 154 to produce stimulation of the body tissues.FIG. 6 illustrates one embodiment of components of the electronicsubassembly and associated units.

In the illustrated embodiment, a processor 204 is generally included inthe electronic subassembly 110 to control the timing and electricalcharacteristics of the stimulator. For example, the processor can, ifdesired, control one or more of the timing, frequency, strength,duration, and waveform of the pulses. In addition, the processor 204 canselect which electrodes can be used to provide stimulation, if desired.In some embodiments, the processor may select which electrode(s) arecathodes and which electrode(s) are anodes. In some embodiments, theprocessor may be used to identify which electrodes provide the mostuseful stimulation of the desired tissue. This process may be performedusing an external programming unit, as described below, which is incommunication with the processor 204.

Any processor can be used and can be as simple as an electronic devicethat produces pulses at a regular interval or the processor can becapable of receiving and interpreting instructions from an externalprogramming unit 208 that allows modification of pulse characteristics.In the illustrated embodiment in FIG. 6, the processor 204 is coupled toa receiver 202 which, in turn, is coupled to the optional antenna 124.This allows the processor to receive instructions from an externalsource to direct the pulse characteristics and the selection ofelectrodes, if desired.

In one embodiment, the antenna 124 is capable of receiving signals(e.g., RF signals) from an external telemetry unit 206 which isprogrammed by a programming unit 208. The programming unit 208 can beexternal to, or part of, the telemetry unit 206. The telemetry unit 206can be a device that is worn on the skin of the user or can be carriedby the user and can have a form similar to a pager or cellular phone, ifdesired. As another alternative, the telemetry unit may not be worn orcarried by the user but may only be available at a home station or at aclinician's office. The programming unit 208 can be any unit that canprovide information to the telemetry unit for transmission to thestimulator. The programming unit 208 can be part of the telemetry unit206 or can provide signals or information to the telemetry unit via awireless or wired connection. One example of a suitable programming unitis a computer operated by the user or clinician to send signals to thetelemetry unit.

The signals sent to the processor 204 via the antenna 124 and receiver202 can be used to modify or otherwise direct the operation of thestimulator. For example, the signals may be used to modify the pulses ofthe stimulator such as modifying one or more of pulse duration, pulsefrequency, pulse waveform, and pulse strength. The signals may alsodirect the stimulator to cease operation or to start operation or tostart charging the battery. In other embodiments, the electronicsubassembly 110 does not include an antenna 124 or receiver 202 and theprocessor operates as programmed.

Optionally, the stimulator may include a transmitter (not shown) coupledto the processor and antenna for transmitting signals back to thetelemetry unit 206 or another unit capable of receiving the signals. Forexample, the stimulator may transmit signals indicating whether thestimulator is operating properly or not or indicating when the batteryneeds to be charged. The processor may also be capable of transmittinginformation about the pulse characteristics so that a user or cliniciancan determine or verify the characteristics.

The optional antenna 124 can have any form. In one embodiment, theantenna comprises a coiled wire that is wrapped at least partiallyaround the electronic subassembly within or on the housing.

The above specification, examples and data provide a description of themanufacture and use of the composition of the invention. Since manyembodiments of the invention can be made without departing from thespirit and scope of the invention, the invention also resides in theclaims hereinafter appended.

What is claimed as new and desired to be protected by Letters Patent ofthe United States is:
 1. An implantable pulse generator, comprising: asealed chamber; an electronic subassembly disposed in the sealedchamber; a plurality of feed through pins electrically coupled to theelectronic subassembly and extending out of the sealed chamber; aplurality of feed through interconnects, each of the plurality of feedthrough interconnects electrically coupled to a one of the feed throughpins and comprising a first contact pad, a second contact pad, and a tabon the first contact pad and in contact with the one of the feed throughpins; and a lead connector comprising a plurality of connector contactsand configured and arranged to receive a portion of a lead having leadcontacts, wherein the connector contacts are electrically coupled to thesecond contact pads of the feed through interconnects.
 2. Theimplantable pulse generator of claim 1, wherein the tab is configuredand arranged to flex away from the first contact pad.
 3. The implantablepulse generator of claim 2, wherein each of the tabs is flexed away fromthe first contact pad and rests against a side of the one of the feedthrough pins.
 4. The implantable pulse generator of claim 1, whereineach of the first contact pads defines a coupling aperture having afirst edge and an opposing second edge.
 5. The implantable pulsegenerator of claim 4, wherein the tab has a proximal end and an opposingdistal end, and wherein the tab is at least partially disposed over thecoupling aperture with the proximal end of the tab attached to the firstedge of the coupling aperture.
 6. The implantable pulse generator ofclaim 4, wherein at least one of the coupling apertures receives a oneof the feedthrough pins.
 7. The implantable pulse generator of claim 1,wherein the feed through interconnects are spaced apart at uniformdistances.
 8. The implantable pulse generator of claim 1, wherein eachof the tabs is welded or soldered to the one of the feed through pins.9. The implantable pulse generator of claim 1, wherein the leadconnector is a first lead connector and the implantable pulse generatorcomprises a second lead connector disposed adjacent the first leadconnector and comprising a plurality of second connector contacts andconfigured and arranged to receive a portion of a lead having leadcontacts, wherein the second connector contacts are electrically coupledto the second contact pads of the feed through interconnects.
 10. Theimplantable pulse generator of claim 9, wherein the plurality of feedthrough interconnects comprises a plurality of first feed throughinterconnects electrically coupled to the connector contacts of thefirst lead connector and a plurality of second feed throughinterconnects electrically coupled to the second connector contacts ofthe second lead connector.
 11. The implantable pulse generator of claim10, wherein the first feed through interconnects and the second feedthrough interconnects are interleaved.
 12. The implantable pulsegenerator of claim 9, wherein the plurality of feed through pinscomprises a first row of the feed through pins and a second row of thefeed through pins, wherein the first feed through interconnects areelectrically coupled to the first row and the second feed throughinterconnects are electrically coupled to the second row.
 13. Theimplantable pulse generator of claim 12, wherein the feed through pinsof the first row are staggered relative to the feed through pins of thesecond row.
 14. The implantable pulse generator of claim 9, wherein eachof the tabs is flexed away from the first contact pad and rests againstthe one of the feed through pins.
 15. The implantable pulse generator ofclaim 9, wherein each of the first contact pads defines a couplingaperture having a first edge and an opposing second edge.
 16. Theimplantable pulse generator of claim 15, wherein the tab has a proximalend and an opposing distal end, and wherein the tab is at leastpartially disposed over the coupling aperture with the proximal end ofthe tab attached to the first edge of the coupling aperture.
 17. Theimplantable pulse generator of claim 15, wherein at least one of thecoupling apertures receives a one of the feedthrough pins.
 18. Theimplantable pulse generator of claim 1, wherein a width of the first andsecond contact pads is greater than a width of an intermediate portionof the feed through connector between the first and second contact pads.19. An electrical stimulation system, comprising the implantable pulsegenerator of claim 1; and a lead having a proximal portion and a distalportion and comprising a plurality of electrodes disposed along thedistal portion of the lead and a plurality of lead contacts disposedalong the proximal portion of the lead.
 20. An electrical stimulationsystem, comprising the implantable pulse generator of claim 9; a firstlead having a proximal portion and a distal portion and comprising aplurality of electrodes disposed along the distal portion of the firstlead and a plurality of lead contacts disposed along the proximalportion of the first lead; and a second lead having a proximal portionand a distal portion and comprising a plurality of electrodes disposedalong the distal portion of the second lead and a plurality of leadcontacts disposed along the proximal portion of the second lead.